When does common selfheal bloom in Oregon?

Most often in July. Across 347 dated, research-grade observations of Prunella vulgaris in Oregon, the flowering season runs roughly June to August.

Peak July In flower 347 Examined 472 State Oregon

Flowering 347 in flower of 472 examined

Proportion of examined Prunella vulgaris in Oregon in flower, by month
Month In flower Examined Share 95% interval
Jan 1 15 7% 1% to 30%
Feb 0 5 0% 0% to 43%
Mar 0 14 0% 0% to 22%
Apr 1 15 7% 1% to 30%
May 12 31 39% 24% to 56%
Jun 150 159 94% 90% to 97%
Jul 114 120 95% 90% to 98%
Aug 33 36 92% 78% to 97%
Sep 12 19 63% 41% to 81%
Oct 12 22 55% 35% to 73%
Nov 4 17 24% 10% to 47%
Dec 8 19 42% 23% to 64%

Peak flowering in Jul. Each bar is the share of Prunella vulgaris in Oregon observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 347 of 472 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.wt38fd.

What this is, and what it is not

This is a record of when people in Oregon found Prunella vulgaris in flower, not a forecast. It is computed only from observations made in Oregon, so it is not the species’ global average dragged onto a map: the same plant flowers on different dates in different places, and that is the entire point of the page.

It will not tell you what your particular plant will do this year. Bloom time moves with the season, with altitude, and with the weather, and a warm February pulls everything forward. We publish the distribution and the sample size, and we refuse to draw a month that too few people examined.

The plant

Sourcesevery claim on this page

  1. GBIF (iNaturalist Research-grade Observations). Dated flowering annotations in Oregon. Every record achieved iNaturalist quality grade Research, which is applied upstream at export. 10.15468/dl.wt38fd. Retrieved 2026-07-14.
  2. World Flora Online Plant List. The accepted name. CC0. Retrieved 2026-07-12.